There has been a cover body structure obtained by welding an inner reinforcing plate having a concave part to an outer panel of construction machinery (for example, see Japanese Patent Application Laid-Open No. 09-228412 (“JP '412”) (e.g., page 3, FIG. 7)).
There has been an engine cover having a sound insulating material or a sound absorbing material as a lining member attached to the inner side of a cover body in construction machinery (for example, see Japanese patent Publication No. 3457804 (“JP '804”) (e.g., page 2, FIG. 1)).
In JP '412, the cover body structure becomes heavy in order to obtain sufficient strength using the inner reinforcing plate, and welding traces tend to appear on the outside. Also, neither sound insulating performance nor sound absorbing performance is sufficient.
In JP '804, the lining member such as the sound absorbing material is visible from the outside when opening the engine cover, creating an unattractive appearance and insufficient strength.
The present invention has been made in consideration of the above-mentioned problems, and it is an object of the present invention to provide a panel capable of obtaining sufficient strength, weight reduction and sound absorbing performance, and a method for manufacturing the panel.